Neue Nationalgalerie is a museum for classical modern art in Berlin, with main focus on early the 20th century. The collection features a number of unique highlights of modern 20th century art. Particularly well represented are Cubism, Expressionism, the Bauhaus and Surrealism. The museum building and its sculpture garden were designed by Ludwig Mies van der Rohe and opened in 1968. The walls of the museum are almost entirely glass, interrupted only with slim metal structural supports, and the white natural light transmitted through these walls reflects off the dark floor.